Over the lifetime of a baby born today — the next 70 to 80 years — Hawaii is poised to see some of the nation’s worst consequences from climate change, experts say.

By mid-century and beyond, scientists predict, Hawaii will begin to experience sea level rise that could inundate tens of thousands of acres in coastal communities, flooding that could cripple tourism centers, and rising temperatures and fluctuations in rainfall that could lead to the disappearance of vital forest ecosystems and marine habitats.

At risk: Nothing less than Hawaii’s visitor-based economy, its watersheds, its environmental diversity, its cultural resources. One recent study said under the worst-case scenario for sea level rise — 10 to 12 feet by 2100 — Hawaii would rank second in the nation for the percentage of its population affected by rising seas: 189,000 people.

And in public presentations, the Hawaii Climate Change Mitigation and Adaptation Commission, which is compiling a report to the Legislature in December, estimated that more than 20,000 residents would be displaced with a 3.2-foot rise in sea levels.

The economic losses to property in that scenario: More than $19 billion.

And those same experts say Hawaii is doing far too little to prepare for the unprecedented threat that climate change poses to the future of the islands.

While the science of climate change continues to evolve — and its potential consequences are coming into sharper focus — scientists and policymakers have known global warming was happening for decades. Even so, adaptation efforts are in their infancy in Hawaii, a situation that’s spurring significant concern for many.

The question some are asking now: Did we wait too long?

“We are behind,” said Vern Miyagi, who is administrator of the Hawaii Emergency Management Agency and serves on the state’s commission on climate change mitigation. “Sea level rise is coming (and) we got to start catching up. We have to come up with options, and some of these options are painful. We need to get ahead of it.”

Sam Lemmo, co-chair of the state commission and administrator of the Office of Conservation and Coastal Lands, was similarly blunt: “We didn’t prepare,” he said. “We don’t have the tools to manage the situation. We’re asking ourselves, what do we do?”

That’s not to say there’s not work underway to determine how to move forward.

But most of the focus is on studies — and lots of them — looking into a host of ways that climate change could affect island life and its environment. And climate change adaptation projects in Hawaii have been on a relatively small scale, though scientists and policymakers hope they hold promise for replication.

One included moving critically endangered indigenous snails in Waianae to higher ground, after modeling showed that their current home at about 2,000 feet above sea level would no longer be hospitable in 40 years (as temperatures rise and the area becomes more arid). Scientists had to move them to Mount Kaala, 4,000 feet above sea level.

The hope: Similar “trans-locations” could happen with other native species.

There’s also a pilot project underway in Lahaina to determine if planned retreat is feasible in Hawaii. The state-funded project is focusing on a single, 10-story timeshare that’s been grappling with beach erosion for years. Today, waves are lapping up against the concrete building and washing into the building’s underground parking lot.

The lessons learned from the pilot could prove invaluable to Waikiki and other coastal communities.

Ramping up similar work over the next few decades will be key, Lemmo said.

“People who live on islands are going to suffer the worst (from climate change’s impacts),” he said recently at a public meeting on the climate change commission’s work. “That’s why we have an interest in attacking this problem. We want to show that we can be … a leader in this area. We’re trying to adjust to these rapidly-changing realities.”

‘We need to get ahead of it’

In June, just two weeks after President Donald Trump announced he was pulling the United States out of the Paris Climate Accord, Hawaii became the first state in the nation to enact portions of the international agreement into law.

Act 32 not only strengthened Hawaii’s commitments to reducing greenhouse gas emissions, it turned a small climate change committee into the wide-reaching state commission — co-chaired by Lemmo — tasked with providing policy direction, coordination and planning on climate change mitigation and adaptation.

The commission’s first step: Its report to the Legislature this winter. Commission members say the comprehensive analysis will seek to quantify the scope of the impacts of sea level rise in Hawaii (other effects will be taken up later), and will make recommendations that will eventually be part of a statewide plan.

In public meetings over the last few months, the commission has unveiled some key conclusions. The group estimates that, for example, 27,000 acres of coastal land would be at risk with 3.2 feet of sea level rise. At 6 feet, that figure goes up to more than 43,000 acres. About 44 percent of that inundated acreage is on Oahu, the commission said.

Meanwhile, the group estimates that with 3.2 feet of global sea level rise, about 116 miles of roadway in Hawaii would be at risk for flooding. Oahu would be the hardest hit, with nearly 70 miles of roads affected. On Kauai, 22 miles would be flooded.

By 2060, models put sea level rise on Oahu at anywhere from 1 foot (a conservative estimate) to 4 feet (the worst case). That worst case would mean inundation into much of Waikiki, Urban Honolulu and the airport. By century’s end, meanwhile, the lowest estimates put water inundation levels at 1.7 feet. The worst case: Nearly 11 feet.

Miyagi, of the emergency management agency, said while the models differ, one certainty exists: Sea level rise is happening. “It’s an increasing hazard. It’s a slow-moving flood event,” he said. “And we need to get ahead of it.”

This summer’s record-high king tides, which have swallowed up whole stretches of Waikiki beach for hours at a time and caused nuisance flooding in areas, underscore the need for quicker action, he said. And they showcase how communities can tackle sea level rise.

In short, Miyagi said, they’ll have to weigh some difficult options.

Those options include exploring how to use limited public monies to move coastal infrastructure, from roads to sewer pipelines, or protect them from the encroaching shore. They also include considering when to sink money into projects that hold back the waves — and when to acknowledge that a “planned retreat” is the only viable choice.

“We got to move things out of the projected flooding areas,” Miyagi said.

Leo Asuncion, director of the state Office of Planning, who also serves on the commission, said mitigation also includes working with developers and government agencies to ensure that new projects are considering climate change impacts.

That’s something that’s already being done to a degree, though it’s voluntary.

And developers are able to plan for any model of sea level rise — conservative or not.

“The reason why that works better is because if government gives a solid number, like plan for 3 feet, and then comes back five years from now and it’s actually going to be 4 feet, you can’t make those guys suddenly change out their plans,” Asuncion said.

He added, “There needs to be some risk that the developer takes.”

‘We’re manning the lifeboats’

Of course, climate change isn’t just about sea level rise.

It’s also about rising temperatures that threaten sensitive ecosystems — and their inhabitants. Climate change will almost certainly change Hawaii’s landscape; some areas will get significantly drier, others wetter, threatening already-ailing forests that are crucial to Hawaii’s water production and the survival of countless native species.

After all, well before the specter of climate change loomed so large, Hawaii was dubbed “the extinction capital of the world.” The U.S. Fish and Wildlife Service lists 1,448 endangered animals and plants; 502 are endemic to Hawaii.

The scientists on the front lines of trying to save those indigenous species say they’ve been in crisis mode for decades — watching the native animals and plants they dedicated their lives to studying disappear before their eyes, despite their best efforts.

Climate change will undoubtedly make their work harder.

Warmer temperatures are already threatening native bird species, as mosquitoes carrying diseases spread into higher elevations. Also facing an uncertain future: The state insect, the Kamehameha butterfly, whose populations are dwindling. And climate change will almost undoubtedly push more varieties of native tree snails into extinction.

Two centuries ago, there were an estimated 750 different types of Hawaiian land snail. They were incredibly abundant in the islands; revered in ancient Hawaiian chants and used to make shell lei. Today, thanks chiefly to invasive predators, half of them have gone extinct.

More than 40, meanwhile, are listed as endangered — and are near extinction.

Caring about native snails might be a tough sell to the average islander, but scientists say they are essential to the health of the forests — and that their rapid degradation is a canary in the coal mine. A warning of bigger problems ahead.

In other words, let the snails die off at our peril.

A small cadre of scientists is trying to avoid that future. And now — along with monitoring snails in a lab and in small field communities behind predator-proof fences — they’re thinking through how to move snails to environments that will remain hospitable, even as climate change dries out and heats up Hawaiian forests at lower elevations.

Key to their work: A lab called the “snail ark.”

It’s in a trailer behind the Castle Medical Center in Kailua, and overseen by the state’s Snail Extinction Prevention program. There, scientists watch over 15 endangered snails — three of which no longer exist in the wild. One of the snails is the last of its kind.

The ark was started by a University of Hawaii professor in the 1980s, and transferred to the state several years ago. It represents one of the options available to scientists as native species already under threat begin to feel the impact of climate change.

If an animal isn’t surviving in the wild, the only choice might be saving it in a lab — rearing animals born in captivity. In the best case, an endangered species is located back to the wild. In the worst, all known examples of a species die off.

David Sischo, the state’s snail extinction prevention program coordinator, said introducing the threat of climate change into his work, while necessary, also feels fairly overwhelming. At the snail ark, he said, “we’re at this point manning the lifeboats.”

Sischo said there is hope that climate change mitigation efforts can be replicated.

But, he added, native land snails are “going extinct as we were talking right now.”

‘Doing something’

This summer, the Union of Concerned Scientists released a state-by-state analysis to underscore how sea level rise will cause chronic flooding in communities nationwide.

Hawaii wasn’t included in the report — the scope of the problem was too big. Climate scientist Kristina Dahl said there just wasn’t enough time to consider sea level rise in the islands.

But she did say Hawaii’s coastal communities, like those across the nation, will soon be faced with some hard choices as nuisance flooding becomes more serious.

By 2100, the report said, about 490 communities nationwide would face chronic inundation under an intermediate model of sea level rise. That figure shoots to 670 under a high scenario.

“Hawaii is such a culturally unique and distinctive place,” Dahl said. “One of the challenges (will be) … figuring out how to preserve that culture and history while also maintaining the economic engine that is the coastlines.”

Indeed, one study estimated the loss of Waikiki beach at $2 billion.

Kupa’a Hee, an artist and conservationist with the snail extinction prevention program, said there's a tendency to focus on the immediate economic impacts of climate change. But, he cautioned, that's short-sighted and could mask the bigger threats Hawaii faces — and their solutions.

“My motivator is I’m actually doing something instead of nothing,” Hee said. “Native species … make Hawaii livable. For people to be worried about, ‘well, Waikiki is going to be gone,’ that’s small peanuts compared to our water source is going to be gone.”

This story part of an ongoing Hawaii News Now digital series exploring climate change and its impacts in Hawaii.